Integration of contraceptive care and sexually transmitted diseases (STD) services for women at high risk for both unplanned pregnancy and STD has the potential of improving overall reproductive health care. This integrated model has been implemented in family planning clinics, where STD screening and treatment services are also offered, but much less so in STD clinics, which serve a different population, often less socially organized and less interested in preventive health care. Although combining ongoing family planning care in an STD clinic has been tested, to date there are no studies evaluating an approach of initiating contraceptive care in an STD clinic followed by facilitated transition to existing primary health care facilities for ongoing family planning services. The purpose of this study is to explore such a model, and, rather than creating a parallel structure of family planning services within the STD clinic setting, determine whether STD clinic-initiated contraceptive care with transition to a primary care provider (PCP) for ongoing care can improve the rate of long-term use of effective contraception among high-risk women and lower the rate of unintended pregnancy. Denver Metro Health Clinic, the STD clinic of the Denver Public Health Department, will conduct a 4-year randomized trial among women attending the clinic who are not consistently using contraception. The program will enroll approximately 1200 such women over the initial 32 months. Potential subjects will be approached about participation when they present for STD services, and those enrolling will be randomly assigned to either an intervention or control group. Women in the intervention group will be counseled by a family planning nurse about contraceptive options and have the method of their choice initiated at either the enrollment or an early follow-up visit, following which they will be assisted with making an appointment with a PCP of their choice for ongoing contraceptive care. Contraceptive methods will include Depo-Provera, oral contraceptive pills, condoms, contraceptive foam, and diaphragms. Women in the control group will be provided brief advice about possible contraceptive options, a 1-month supply of foam and condoms and a standard referral list, with information about clinics and providers they might contact for contraceptive services. Outcomes will be assessed over a year by means of a 4 and 8 month telephone interview, 12-month return visit interview, review of medical records at the clinic of any subsequent PCP and at DMHC, and review of 2 statewide databases of reported STD for STD outcomes and the state's computerized Birth Registry for pregnancy outcomes. Seven study outcomes are targeted, including: 1) initiation of effective contraception; 2) time to initiation of effective contraception; 3) duration of effective contraception; 4) initiation of contact with a PCP; 5) time to initiation of PCP contact; 6) rate of unintended pregnancy; and 7) rate of incident STD. A final evaluable sample of 300 women per group should be sufficient to detect a reduction from 31.5% to 20% in the proportion of women with unintended pregnancy and the possibility of an increase in the rate of incident STD from 10% to 18.3%. Such a program has the potential of addressing comprehensive reproductive care from the context of the STD clinic and, if successful, may offer a useful model for other STD programs to consider.